When coating automobiles and the like, color boundaries are marked with masking tapes. When a masking tape is applied to a curved surface of an automobile bumper, a motorcycle tank and the like, or to an object having raised portions and recessed portions, a masking tape prepared using, as a substrate, a soft vinyl chloride superior in flexibility has been used.
However, a masking tape prepared using soft vinyl chloride as a substrate cannot be simply incinerated after use, since chlorine gas is generated by incineration. To avoid this, a device for removing chlorine gas is required to be set on the incinerator. In view of such problem, a material has been desired which can be incinerated without problems.
A useful substitute for the soft vinyl chloride may be a polyolefin material. Generally speaking, however, polyolefin materials are associated with a problem that, as seen in polyethylene and the like, constriction called "necking" occurs locally when it is drawn, and a straight parting line cannot be formed. In addition, due to low flexibility, polypropylene hardly follows the irregularities in the surface to which it is to be adhered, thus posing another problem besides the necking.
As set forth above, a conventional masking tape-prepared using a polyolefin substrate film cannot produce a sufficient parting line on the above-mentioned surfaces having irregularities.
It is therefore an object of the present invention to provide a masking tape free of the above-mentioned problems, which is capable of precisely following the shape of curved adhesion surfaces of, for example, automobile bumpers and motorcycle tanks, and capable of providing fine parting lines.